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<html lang="en">
<head>
    <meta charset="UTF-8">
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    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
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<body>
    <script>
        var str = 'hello world pink green orange blue black brown';
        var strs = str.split(' ');
        var strCon = strs.join('-');
        console.log(str);
        console.log(strs);
        console.log(strCon);
        console.log(str2 = str.toUpperCase());
        console.log(str2.toLowerCase());
    </script>
</body>
</html>